Overview of building simulation in Europe

Slides from a presentation which provides and overview of building simulation in Europe

An engineering approach to modelling of dynamic insulation using ESP-r

The use of Dynamic Insulation (DI) can enable recovery of conduction heat loss through a building envelope. This is an active process that allows air to move through the fabric against the temperature gradient. Additionally it promises better indoor air quality, primarily due to filtration properties of the construction material [11]. This paper is concerned with quantifying the energy savings and enhancement of human comfort if this technology is integrated into a building. To ascertain the impact of the technology on whole-building performance, it is necessary to undertake detailed dynamic modelling. A suitable building and plant simulation computer tool (ESP-r) was employed to do this. A technique for modelling the dynamic insulation was developed and validated against known analytical solutions. A full-size test house was then simulated, in the UK climate, with and without DI. Comparative results show that better thermal comfort and energy savings are possible with the use of DI. The results obtained have been translated into suggestions for best practice

The effect of external surface properties on the thermal behaviour of a transparently insulated wall

The properties of transparent plaster covering transparent insulation materials (TIM) were investigated using a whole building simulation program (ESP-r). The outer plaster was made from glass balls of different diameter, glued together with synthetic resin. The transmittance of the whole transparent covering layer (plaster + TIM) was estimated for different solar incident angles by laboratory measurements. The innovative character of the materials required refining of ESP-r's optical database in order to take into account these new characteristics. The transparently insulated building facade was proposed as a solar energy storage system. The results of the initial analysis showed the desirable optical properties, estimated for sun incident angles on the façade at a latitude of 52 degrees north. Then, simulations based on real climatic data for Central Europe were conducted to predict the thermal TIM wall behaviour. The influence of the structure on the diurnal heat storage potential was investigated for selected periods of the year

Comparison of the simplified methods of the ISO 13790 standard and detailed modelling programs in a regulatory context

The CEN Standards that support the European Energy Performance of Buildings Directive requirement for calculation of the energy consumption of buildings allow various methods to be used for the same calculation. The impact of using the different methods within the updated ISO 13790 Standard for space heating and cooling energy calculations was examined with a parametric analysis of a common building specification. The impact was assessed by considering the energy band which would be assigned for the building based on the calculation results. The Standard describes three different methods that can be used for the calculations: a monthly quasi-steady state method, a simplified hourly method and detailed simulation. For most cases studied, differences in the building rating given by the various methods were a maximum of one band. More significant differences were noticed in some cases. Parameter values in the monthly method were determined which would lead to improved matching

Achieving a holistic view of the life cycle performance of existing dwellings

Models which fully evaluate the life cycle energy and greenhouse gas (GHG) emissions of national housing stocks are not reported in literature. Capturing a holistic view of energy and emissions of the residential sector is an important process that can lead to a more effective policy making. This paper presents a methodology which evaluates the life cycle energy and GHG emissions of retrofitting housing stocks considering all life cycle stages and incorporating, to the greatest extent possible, all upstream inputs. To achieve this, we developed a hybrid model of the existing Irish housing stock, comprising a process-based approach supplemented by input-output LCA for installation of materials and fit-outs and maintenance of appliances. Life cycle analysis (LCA) is a commonly accepted technique for evaluating cradle-to-grave environmental impacts of a product. Using an assumed 50-year life span in all cases, representative archetypes were used to estimate the performance along retro fitting, operation, maintenance and disassembly phases of the three selected house retrofit scenarios: BaseCase (no interven- tion), Current Standards (retrofitting to meet current building regulations) and Passive House (retrofitting to meet Passive House Standards). Results show that detached houses displayed the highest range of life cycle energy and exhibited the greatest absolute and percentage reductions compared to other house types, as life cycle energy ranges from 386-614 kWh/m2yr, 225-261 kWh/m2yr and 126-137 kWh/m2yr for all house scenarios, respectively. Using these results an assessment is provided for policy makers on a holistic view of the life cycle performance of existing dwellings

Impact of using different models in practice - a case study with the simplified methods of ISO 13790 standard and detailed modelling programs

The updated ISO 13790 Standard is part of the new set of CEN Standards that supports the European Energy Performance of Buildings Directive (EPBD) requirement for a general framework for calculation of the energy consumption of buildings. The Standard sets out procedures for space heating and cooling energy calculations, allowing the use of three different methods: a simplified monthly quasi-steady state method, a simple-hourly method and detailed simulation. This paper examines the implications of allowing different methods to be used for assessing the energy usage. The research method used was to undertake a comparison of the various methods applied to a common building specification, with parametric analyses of variations in this specification. The paper discusses differences in results for heating and cooling requirements between the simplified methods and when a detailed simulation program (ESP-r) is used with constrained (according to the Standard) inputs and with a number of unconstrained inputs. The case where two different detailed simulation programs (ESP-r and EnergyPlus) are used in practice for the same building is also included and conclusions are drawn regarding the practical use of different detailed modelling programs against the simplified methods, as well as against each other

Trends in office internal gains and the impact on space heating and cooling demands

Internal gains from occupants, equipment and lighting contribute a significant proportion of the heat gains in an office space. Looking at trends in Generation-Y, it appears there are two diverging paths for future ICT demand: one where energy demand is carefully regulated and the other where productivity enhancers such as multiple monitors and media walls causes an explosion of energy demand within the space. These internal gains scenarios were simulated on a variety of different building archetypes to test their influence on the space heating and cooling demand. It was demonstrated that in offices with a high quality facade, internal gains are the dominant factor. As a case study, it was shown that natural ventilation is only possible when the ICT demand is carefully regulated

Estimation of the carbon footprint of student halls of residence in the University of Strathclyde

There is a rapid increase in environmental awareness, which has led to legislative and governmental policy developments addressing the reduction in carbon emissions to the atmosphere. As an example of a local level response, the University of Strathclyde has developed its Environmental Management System. This paper presents the detailed estimation of the carbon footprint of one of the University halls of residence that will assist the University in assessing its environmental impact. The procedure adopted, and the sensitivity studies undertaken, will help to inform the extension of the carbon footprint study to the whole university campus

Communal residential laundry washing and drying : can it provide demand-side electrical load flexibility?

Changes in lifestyle have led to increased use and ownership rates of domestic appliances resulting in increasing electrical consumption in the residential sector. An important element of this consumption is due to domestic washing and drying of laundry. Given current and predicted ownership rates, the market for drying facilities is still not fully saturated and electrical demand for these functions will therefore increase. This paper looks at energy loads for laundering in high density housing such as blocks of flats and explores the benefits of communal facilities. Benefits of such facilities include reduced high humidity levels and the mitigation of decreased indoor air quality associated with indoor drying of laundry in individual dwellings. However from the perspective of integrating microgeneration into buildings, communal facilities may facilitate increased flexibility in the electrical demand profile, hence better complementing low carbon and localised energy supplies. In order to investigate the possible effects on the electric demand load profile, this paper presents the scenario of a hypothetical housing block and analyses the effect of moving from washing and drying in individual households to communal facilities. The study includes the effects of appliance energy-efficiency improvements and increased ownership rates. Results obtained show that communal laundering is successful in terms of time-shifting and hence lowering of peak electrical demand but is ineffective in reducing consumption